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After a 2 year absence, “Dipsy” the Diplodocus is back at HMNS! Making it’s debut back in 1975, Dipsy was the first dinosaur to call HMNS home. In 2013, our Diplodocus was de-installed from its original place in the Glassell Hall and sent off for a much needed spa retreat in Utah. While there, the bones were carefully cleaned and a new mounting frame designed. This week, she arrived back in Houston and was permanently installed in our Morian Hall of Paleontology.

Spine, tail and rib bones go up first. Followed by the legs.

Front leg installation: Dipsy’s stance has been modified from it’s previous posture. Now, the skeleton assumes a tripod stance, as if rearing up to feed on leaves.

This particular Diplodocus skeleton is a holotype for Diplodocus hayii. A holotype is a single physical example (or illustration) of an organism, known to have been used when the species was formally described. HMNS is the only place in the world where you can see a Diplodocus hayii on display.

Paleontologists don’t know for sure whether Dipsy is male or female.

Diplodocus hayii were herbivores. Their skulls, however, have many small, sharp teeth. These were used for stripping plants, not for chewing.

This skeleton is 72 feet long and about 25 feet high.

Dipsy’s skull was the last piece to be installed. Notice the small, sharp teeth present.

For those of you who have been going to HMNS for years, you may have noticed that we’ve been missing a rather large lady from our Hall of Paleontology. Our Diplodocus, “Dipsy”, was Houston’s first dinosaur unveiled in 1975 and she was de-installed in September 2013. This was her first trip from home for a well-deserved cleaning. Luckily, she’s due back at HMNS in March! We’re so excited for her to be back that we’ve even put her on our overnight shirts! In honor of her return, we’ve dedicated this month’s Educator How-to to this dynamic Diplodocus.

Dipsy can teach us quite a few things about balance! When we first installed Dispy in 1975, she was a tail dragging dino as you can see in the photo below. With further studies, they realized that large dinosaurs like the Diplodocus couldn’t possibly walk with their tail on the ground. Think of all the friction and weight! Instead, they realized that they must have used their tail as a counterbalance for their long neck and head like you can see in the illustration below. To demonstrate how Dipsy uses balance, we are going to make a balancing Dipsy!

Dispy’s early days at HMNS had her dragging her tail on the ground.

Illustration of Dipsy using her tail for balance on our HMNS Overnight shirts.

4. If you try to balance her now, you may notice that she’s not very good at it. We need to add weight to correct her center of mass.

5. In this case we are going to use paperclips! Add paperclips to Dipsy to get her to balance. Since she is a very large and currently top-heavy dinosaur, we need to add lots of weight down low to keep her balanced. I’ve added three paperclips per foot.

6. If your students would like more of a challenge, have the students adjust the position of the paperclips and watch as her balancing point changes. See if they can get her to balance using different sized paperclips or changing the location of the paperclips.

The point on which something balances is in line with its center of mass. The object will be most stable (and easier to balance) if the center of mass is below the balancing point instead of above it. For regularly shaped objects like a rectangular sheet of paper the center of mass is the geometric center of the object, but it depends on the shape of the object and how the weight is distributed (imagine adding a bunch of paperclips to one side of an index card and then balancing it horizontally on a pencil eraser – the center of mass and the balancing point will be closer to one edge now).

For our Balancing Dipsy, the object is an unusual shape and has unusual weight distribution. We needed to add weights to our Balancing Dipsy to make her center of mass below where we place our finger when she is upright. With enough weight we can get Dipsy to balance on our finger or a pencil!

Dipsy is just one of many dinosaurs that use their tails to balance. On your next field trip to HMNS, you can see several dinosaurs in the Morian Hall of Paleontology that have their tails sticking out for balance. See if you can find them all! While you’re here, you can bring your own Balancing Dipsy to see our very Dipsy the Diplodocus. She’ll be back this March!

Editor’s Note: This post is the first in a series featuring influential women from STEM (Science, Technology, Engineering and Math) fields in the lead up to HMNS’ annual GEMS (Girls Exploring Math and Science) event, February 21, 2015. Click here to get involved!

In the early 1800s, discoveries made by Mary Anning greatly expanded the field of paleontology and shed light on many previously undiscovered prehistoric creatures. Born in 1799 to a lower class family, Mary and her brother Joseph grew up wandering the shores of Lyme Regis, England looking for all sorts of fossils. After her father died in 1810, Mary’s fossil hobby became the source of income for the Anning family.

The first major find for the Anning family was a skull of what appeared to be a prehistoric crocodile. Mary’s brother Joseph discovered the skull in 1810, and after a year of meticulous searching, Mary discovered the rest of the skeleton in 1811 at age 12.

The fossilized remains were not from a crocodile as previously thought. In fact, they were remains from a new ocean reptile species which museum scientists named Ichthyosaur. Mary is credited with finding the first Ichthyosaur specimen acknowledged by the Geological Society of London. Her discovery led to discoveries of other Ichthyosaurs in Germany including one nicknamed “Jurassic Mom” which is on display at HMNS in the Morian Hall of Paleontology.

Reconstruction of an Ichthyosaur

But Mary’s contributions to Paleontology didn’t stop there!

In 1823, Mary discovered another ocean reptile named Plesiosaurus. This long-necked ocean reptile had flippers and a skull with sharp interlocking teeth. Her findings showed that the Jurassic seas were filled with all types of sea monsters and things that they left behind. Anning was able to deduce aspects of the Ichthyosaur diet by finding fossilized Ichthyosaur feces containing fish scales, squid suction cups, and belemnites. In addition to her ancient sea life discoveries, Anning also uncovered the first pterodactyl found outside of Germany.

A fossil of Dimorphodon, discovered by Anning.

Over the course of her life, Mary discovered several species of Ichthyosaur and several complete Plesiosaurus skeletons among other fossilized remains. She sold these fossils to numerous museums and private collectors.

Unfortunately, due to her social status,Anning was not credited for many of her discoveries during her lifetime. However, before her death in 1847, Anning became the first Honorary Member of the New Dorset County Museum, and today she is still recognized today as one of the great female contributors to Paleontology!

HMNS is highlighting females that made contributions to STEM fields leading up to our annual GEMS (Girls Exploring Math and Science) event, February 21, 2015!

Although Mary Anning did not have much formal education, she taught herself geology and anatomy to help her find and identify fossils. Her enthusiasm for education helped her expand the knowledge of ancient ocean reptiles.

Girls Exploring Math and Science (GEMS) is an event that showcases some of the great things girls do with science, technology, engineering and math! Students can present a project on a STEM related subject for the chance to earn prize money for their school.

I had other interests — I was enraptured by sculpture and took the fabled freshman History of Art course. The collage shown here was taped together during the lectures on the Renaissance renewal of anatomically correct human form made famous by Greek sculptors. Last month, I found the collage in an old notebook, in the garage, under my copy of American Battleships, a Design History. (That’s for a future blog on the U.S.S. Texas.)

The tiny dinosaur is Podokesaurus — at the time, one of two famous bantam-weight predators of the Late Triassic and earliest Jurassic, the first chapters in dinosaur history. I knew the critter well because it was dug from the red beds of the Great Triassic/Jurassic Valley. Those fossil-rich sandstones and shales filled a rift valley that extended from Nova Scotia to the Carolinas. The rift was as big as the East African Rift we see today.

Smack dab in the middle of the Triassic/Jurassic Valley was New Jersey, where I grew up. Not far north from my house were the Palisades and Granton Quarry, where Triassic flying reptiles had been discovered, plus long-snouted phytosaurs like our HMNS Smilosuchus, plus dino footprints.

The reason I applied to Yale was mostly because it had a museum chock full of red beds specimens. When I visited in 1963, Yale had a cast of the podokesaur skeleton on display — sadly, the original was destroyed by fire 50 years previously. Next to the cast was a lively life-sized sculpture, done by the Yale curator Richard Swann Lull.

“Nifty!” I thought. “Art and paleontology combined! This is the place for me.” The Yale museum was super hospitable to freshmen. I got a job cleaning a Triassic red beds skull — not a dino, but a bizarre plant-eating reptile, woodchuck-sized, with spikes coming out of the head like a tricked-out horned toad. These fellows must have lived in colonies. A bunch were dug from a small area in New Jersey. Podokesaurs surely chased these prickly morsels.

Late Triassic, New Jersey. A colony of vegetarian Hypsognathus emerges from its burrow. Maybe they had been hiding from podokesaurs. Maybe they had been watching Jersey favorite The Sopranos on HBO. Texas was host to a similar reptile. Extra points if you can find it in our Triassic mural.

Freshman year also introduced me to the tradition of the “mixer” — parties where Yalies and young women from nearby colleges co-mingled. At a Mt. Holyoke mixer, I got an earful from female geology students who were steamed, justifiably, about gender bias. Old fogey Yale profs grumbled that “girls can’t lift heavy rocks […] can’t do serious fossil work.” Podokesaurus was a counterargument. It was discovered in 1910 by none other than Dr. Mignon Talbot, who was chair of the geology department. Talbot did her Yale Ph.D. on sea-lilies, crinoids, relatives of starfish that were abundant in Devonian rocks of New York State (we have some fab Jurassic crinoids in our hall). Dr. Talbot went on to become president of the college.

The Wikipedia portrait of Dr. Talbot. The label must’ve been written by a Yale professor.

Even though, as college president, she out-ranked most of the Yale faculty of her time, they insisted on calling her “Miss Talbot” instead of “Dr. Talbot.”Yeesh. In 1965, the Yale director of graduate studies told me “Bob, we shouldn’t give Ph.D.s to girls … they’ll just get married and have babies.” Double yeesh!

Since the one and only skeleton of the pro-compy is missing key parts, Dr. Talbot’s graceful Podokesaurus was used to fill in the blanks and give a general portrait of the fox-sized predators of the Late Triassic. Talbot’s creature gained more fame when it became the inspiration for an entire family, the Podokesauridae.

Later in the twentieth century more species were added to the podoke clan, including Coelophysis from New Mexico. The New York museums scored a mass grave of Coelophysis in the 1940s and 1950s: dozens of skeletons from adults two yards long to babies as small as Podokesaurus and Procompsognathus.

Proud members of the Family Podokesauridae. Coeolphysis grew to seven feet long. Check out the pubis in these guys!

IMPORTANT WARNING! The Jurassic Park franchise uses two names for tiny Triassic dinos: “pro-compy” and “compy”. There might be confusion among the dino-laity.

The true Compsognathus is Late Jurassic, with kin in the Early Cretaceous, and it doesn’t have podoke family values. As we’ll see in a bit, Crichton clearly meant his tiny carnivores to be classic Late Triassic/Early Jurassic carnivores — and that means podokesaurs.

The podokes had a near-monopoly in the meat-eating role in the Late Triassic/Early Jurassic. They were not only small and mid-sized carnivores, equivalent to kit foxes, coyotes and wolves, but they became the movers and shakers in the apex predator role. Big species attained lengths of 22 feet and weights approaching a ton — bigger than the biggest land meat-eaters today (grizzly and polar bears). All podoke species had that graceful build of Dr. Talbot’s Podokesaurus: supple neck, long torso, and outstandingly elongated tail.

For Jurassic Park fans, Procompsognathus rings a bell. In Michael Crichton’s novel, the first dino we get to know is tweensey (but deadly) — a species identified as a pro-compy. These blood-thirsty characters are fond of jumping into perambulators and biting the faces of juvenile humans. They move in gangs. Crichton was dead-on here. Tracks from the Triassic/Jurassic do document podoke-packs, small carnivores cavorting in groups.

Podoke dance floor? Slab of shale with a dozen small predators cavorting.

In the Jurassic Park movie, the pro-compys are unstoppable nasties who confront the gifted character actor, Wayne Knight (Newman) of Seinfeld fame. (Knight’s best known for portraying portly and disreputable men, but we should remember that he was a dashing romantic lead in Third Rock from the Sun.)

In JurassicPark, Knight’s character learns a lesson — the hard way. At first, he insults the pro-compys and tries to scare them away. Then they flash their threat-collars, a device cribbed from the Australian Frilled-Lizard. Then they hurl loogies of what seems to be venomous schmaltz. Nice scene. Scary.

However, dino-nerds: watch out. There are no bones in the lizard collar so preservation in a skeleton would be unlikely. Plus, threat collars are unknown among the many dinos now represented by fossils with skin.

Plus, plus, no dino could spit. Spitting requires complex lip and face muscles of the sort a trombonist must have (didja know I was first-trombonist in the school band?). Reptiles can’t spit, birds can’t spit. Fossil dino faces show that the big, complicated lips just weren’t there.

Spitting cobras cheat. They don’t really spit. They have mouth muscles that squeeze the poison gland so the venom comes squirting out through the hollow fangs. Clever, but not a genuine spit.

Crichton used his dinos carefully. He fills Jurassic Park and Lost World novels with a lovely time-safari through the Mesozoic. He begins with the pro-compy, from the earliest slice of dino-time, about 210 million years ago. The long-necked brachiosaurs and stegos filled out the later Jurassic, some 145 million years ago. You could add a true Compsognathus here if you like. For the Early Cretaceous, 110 million years ago, we are givenDeinonychus antirrhopus (labeledVelociraptor but actually Deinonychus).Triceratops, T. rex and the advanced ostrich-dinos fill out the last slice of Cretaceous, the Lancian Age, 66 million years ago. You can teach an entire paleo course with this fine selection of fossils.

Remember, in the books and movies the label “pro-compy” and “compy” is synonymous with the podokesaurs. Crichton did not intend his Triassic dino to be a Compsognathus, the Late Jurassic animal quite different in body plan from the podokesaurs. Here’s where dilophosaurs come in.

Dilophosaurus, sensu stricto, is a Southwest Early Jurassic apex meat-eater — a big brother of Coelophysis and Podokesaurus. The first specimens were announced by the Berkeley museum in the 1950s. Size: near maximum for the podoke family, nearly 2,000 pounds soaking wet. Our Chinese colleagues excavated a super diloph of the same body mass. In each and every bony bump, the dilophosaur is built to the same basic plan used for Coelophysis, et al. Big difference, besides size, is the side-by-side bone crests on the head.

The Berkeley diloph. Black and white photo shows first restoration of head without crests. Color snapshot shows the crests added. Michelangelo’s David in for scale. Do note that this is a biggish predatory dino.

In the books, Crichton does not describe any head ornaments for his pro-compys. The movie, on the other hand, gives the little fellows side-by-side crests, perfect miniatures of what true dilophs have. I go to screenings of the JP franchise every chance I get (“JP” is what we insiders call Jurassic Park). When I saw the 3D version on the HMNS Giant Screen, I was treated to massive vibrations that punctuated the scary parts.

“Dilophosaurus … DILOPHOSAURUS!” shouted the five-year-old sitting behind me. He was kicking the back of my seat with unconstrained enthusiasm. Can’t blame the kid. He had his plastic diloph in his lap, evidently a cherished pet and quite accurate in most anatomical details (neck and ankle too long, too skinny). The extreme close-ups of the pro-compy head on the screen did look diloph-y. But … the size was as wrong as wrong can be and still stay within the podoke family.

Plastic dilophosaur, by Safari Ltd. About $9 at the Museum Store, with your member discount.

I was tempted to turn around and issue a correction: “Hey kid, that dino is a hundred times too small …” But I restrained myself. I estimated that the leader of the movie pro-compy pack was no more than 15 pounds, Boston Terrier-sized. With head crests, size matters. Small podokes don’t have much in the way of cranial protuberances. All the big crests are on big heads attached to big bodies.

Want to be a podokesaur? You must get a nose-notch. Coelophysis here has one.

And … there was something more, something missing from the schnoz in the movie compy. “No nose notch …” I said to myself. “Those guys in the movie have no nose notch … so … they aren’t members of the Family Podokesauridae!”

Notches below the hole for the nostril are a big deal in dinos and dino-kin. Land Croc-oids of the Triassic, second cousins of dinosaurs, usually are notched. But strong notches are rare amongst the carnivorous dinosaurians. T. rex is notch-less. So isAllosaurus and all the myriad raptors, from Micro-raptor to Meso-raptor to Mega-raptor. The bona fide Compsognthus is notch-less. The podoke family is the most consistently notched. Enjoy my own diagram of the Harvard skull from Coelophysis above. Please stare at the nose. There’s a notch here. Dilophosaurus has an even more emphatic notch.

No notch = no podokesaurid. Simple as that.

What about that long, slanty pubis, another hallmark of the podoke family? Study the movie dino as long as you like. You will find no unambiguous evidence of long, slanty pubic bones. None.

My conclusion: the movie artists did a great job with the pro-compys. They cobbled together a frightening chimaera from a bunch of critters, some lizards, some small meat-eating dinos, some big ones. These little dinos are the most imaginative, most mixed-up of all the JP creations. So enjoy them! But you cannot use the movie pro-compys to teach a lesson in dilophosaurs or any dilophosaur kin. The movie “compy/pro-compy” is NOT a crested podokesaur.

* Recently, some paleontologists have insisted using the name Family Coelophysidae to replace Podokesauridae, because we have so many skeletons of Coelophysis. These folks are well-meaning but, ahem, I am a Yalie and so I am sworn to defend the honor of Mt. Holyoke College and all its faculty and graduates. And its presidents. And its dinosaurs.